I. Field of the Invention
The instant invention relates to a method and apparatus for applying covers to seat cushions to form finished seats such as are often provided in motor vehicles.
The invention particularly pertains to the manufacture of seats with stressed covers which conform tightly to inner cushion material (such as material commonly employed in vehicle seats) which material is usually resilient and deformable. The resulting seats embody covers which follow the contours of the cushions without slackness.
II. Prior Art
Seats of the type to which the instant invention pertains comprise resilient compressible foam cushions, and covers which may be of synthetic materials and which are normally shaped to generally conform to the shape of the finished seat. Normally these covers are of a smaller size than the cushion material to be enclosed by the cover. Accordingly the foam core must be compressed in order to place the cover over the cushion.
Seats of this type often also comprise an innerspring structure with a peripheral frame which forms a means for supporting a cushion and provides the major support for the seat. As is known, the cover in such seats must be forced over the cushion's upper face, then down the sides of the cushion, then pulled inwardly beneath the spring frame, and finally secured to the frame by hog-tying or like means. It is known to provide a work place support for the seat which holds the frame and cushion in an upright position in which the cover can be forced over the top and down the sides of the cushion. Once this is accomplished it is also known to rotate the cushion 180 .degree., fix it in position once again and, while the frame is still held by the support, pull the cover ends over the innerspring frame, and lastly hog-tie the cover in position.
According to the known methods and apparatus, workers must physically pull and tug the cover over the top of the cushion, and after the inversion of the cushion, they must pull the cover upwardly and over the lower half of the cushion, then the cover must be pulled over the spring frame before the cover can be hog-tied to the frame.